IBM Puts Brain On-a-Chip

PORTLAND, Ore. -- The most brain-like computer chip to date has been produced by IBM for the Defense Advanced Research Project Agency's (DARPA's) Systems of Neuromorphic Adaptive Plastic Scalable Electronics (SyNAPSE) program, in collaboration with Cornell Tech and iniLabs, Ltd.

"When the SyNAPSE project was launched six years ago, many people thought it was impossible," Dharmendra Modha, an IBM fellow and chief scientist of brain-inspired Computing at IBM Research, told EE Times. "But today we have proven that it is possible, and we are working toward making it a commercial reality in the future."

IBM's neurosynaptic processor integrates 1 million neurons and 256 million synapses on a single silicon chip.(Source: IBM)

"With 5.4 billion transistors, it is the biggest chip IBM has ever made, and as far as we know is the biggest chip anyone has ever made, and yet it consumes just 70 milliWatts of power," Modha said.

To measure the performance of this mammoth chip, IBM had to invent a new metric, synaptic operations per second, (SOPS) to replace floating point operations per second (FLOPS).

"The chip delivers 46 billion SOPS per Watt -- literally a supercomputer the size of a postage stamp, with the weight of a feather and using a power source the size of a hearing aide battery," Modha said. "It's ideal for monitoring sensors, mobile devices, executing cloud services, and supercomputing."

The architecture consumes 20 milliWatts per square centimeter, which is more than 5,000 times cooler than the power required by today's microprocessors. This chip's architecture is based on an earlier chip with a single neurosynaptic core containing 256 neurons. In this second-generation chip, IBM reduced the area by 15 times, reduced the power by 100 times, and increased the number of cores per chip to 4,096.

The cores are connected by an on-chip mesh network with direct connections between adjacent chips. When tiled, they seamlessly connect to one another in order to form a foundation for future neurosynaptic supercomputers. To demonstrate its scalability, IBM showed a 16-chip system which extended the architecture to 16 million programmable neurons and 4 billion programmable synapses, with the eventual goal of achieving human brain-sized systems of 100 trillion synapses or more.

"We believe this chip establishes a new landmark in neurosynaptic computers with a radical new architecture, unparalleled scale, speed, power efficiency, and boundless scalability," Modha said.

The layout of the chip (left) is composed of 64x64 array of neuro-synaptic cores, each of which (right) implements 256 neurons and 65,536 synapses for tightly integrated computation, memory, and communication.(Source: IBM)